1. Field of the Invention
This invention relates to disk drive suspensions, and more particularly to improvements in limiter-featured disk drive suspensions comprising a load beam and attached thereto a flexure comprising a flexure frame and a flexure tongue adapted to carry a slider for increased load-unload efficiency. The invention provides an improved form of limiter structure to that blocks undue movement of the flexure tongue relative to the flexure frame by engaging the tongue free end with the frame in response to an undue excursion of the tongue. The tongue free end-flexure frame contact is localized to a single locus on the tongue free end. This locus is centrally located to avoid possible tipping of the tongue that can occur when outboard limiter structures at the edges of the tongue free end are employed owing to a possible difference in time of engagement. Non-simultaneous engaging contact of the limiters can tip the slider by first raising only one side of the tongue. This does not occur in this invention, since the limiter engagement locus is centrally located and unitary and thus incapable of not being uniform in time of engagement.
2. Related Art
Limiter structures are broadly known. They are generally designed to either prevent excessive excursions during shock events such as the jarring or dropping of the computer, or to prevent damage to the suspension during loading and unloading cycles. These two situations have different requirements. In load-unload, the slider is lifted from the disk against the forces holding it in position including spring loading by the suspension and the vacuum developed between the slider and the rotating disk. Load-unload cycles in present computers occur frequently, particularly in laptop computers, in an effort to conserve power and thus prolong battery life.
It has been suggested to limit flexure tongue travel with slot and tab arrangements with the tab interfitting the slot, the tab extending typically from the load beam and the slot in the tongue, or vice-versa, with fold-over tabs extending from the load beam and embracing the flexure so as to limit the flexure tongue travel, and with expandable ribbons linking the tongue free end with the opposing frame, or attached to the load beam, but these expedients are more complex to satisfactorily manufacture and may be too costly.